JPS59185005A - Multi-channel reproducing circuit - Google Patents
Multi-channel reproducing circuitInfo
- Publication number
- JPS59185005A JPS59185005A JP5684183A JP5684183A JPS59185005A JP S59185005 A JPS59185005 A JP S59185005A JP 5684183 A JP5684183 A JP 5684183A JP 5684183 A JP5684183 A JP 5684183A JP S59185005 A JPS59185005 A JP S59185005A
- Authority
- JP
- Japan
- Prior art keywords
- terminals
- amplifier circuit
- circuit
- current source
- amplifier circuits
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/127—Structure or manufacture of heads, e.g. inductive
- G11B5/33—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only
- G11B5/39—Structure or manufacture of flux-sensitive heads, i.e. for reproduction only; Combination of such heads with means for recording or erasing only using magneto-resistive devices or effects
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
- G11B5/02—Recording, reproducing, or erasing methods; Read, write or erase circuits therefor
Landscapes
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Recording Or Reproducing By Magnetic Means (AREA)
Abstract
Description
【発明の詳細な説明】
（利用分野）
本発明は、省電力化に適した多チヤンネル再生回路に関
する。DETAILED DESCRIPTION OF THE INVENTION (Field of Application) The present invention relates to a multi-channel reproduction circuit suitable for power saving.
（背 景）
第１図に磁気抵抗効果ヘッドを用いた多チヤンネル再生
回路の例を示す。第１図において、それぞれの磁気抵抗
効果ヘッド２，４．６ｉζ定電流諒１、３．５が接続さ
れており、また、これらの磁気抵抗効果ヘッドと定電流
源との接続点の各々には増幅器７，８．９の入力側が接
続されている。(Background) Figure 1 shows an example of a multichannel reproduction circuit using a magnetoresistive head. In FIG. 1, respective magnetoresistive heads 2, 4.6iζ constant current sources 1, 3.5 are connected, and each connection point between these magnetoresistive heads and a constant current source has a The input sides of amplifiers 7, 8.9 are connected.
一般に、磁気効果ヘッドの抵抗直は小さく、しかもその
抵抗変化率も非常に小さい（約１％）。Generally, the resistance of a magnetic effect head is small, and the rate of change in resistance is also very small (approximately 1%).
このため、該定電流源１，３．５の電流は約１０ｍＡ〜
２０ｍＡ流す必要がある。したがって、第１図に示す従
来例のようにチャンネル数だけの定電流源を用いた回路
ではこれらの定電流源で消費される電力が大きくなって
しまうという欠点がある。Therefore, the current of the constant current sources 1 and 3.5 is approximately 10 mA to
It is necessary to flow 20mA. Therefore, a circuit using constant current sources equal to the number of channels, such as the conventional example shown in FIG. 1, has the disadvantage that the power consumed by these constant current sources becomes large.
また該磁気抵抗効果ヘッドの抵抗変化率が小さいため、
該磁気抵抗効果ヘッド２，４．６に現われる信号電圧は
数百μＶ程度である。したがって、該増幅回路７，８．
９のダイナミックレンジは小さくてすむ。しかしながら
、第１図の従来回路では該増幅回路？、８．９の電源を
電圧源１０よシ並列に供給しているため、上述した該定
電流源と同様にこれらの増幅回路で消費される電力が太
きいという欠点がある。In addition, since the rate of resistance change of the magnetoresistive head is small,
The signal voltage appearing on the magnetoresistive head 2, 4.6 is on the order of several hundred μV. Therefore, the amplifier circuits 7, 8 .
9 has a small dynamic range. However, in the conventional circuit shown in Fig. 1, is the amplifier circuit? .
（目 的）
本発明の目的は、前記した従来技術の欠点を除去し、多
チヤンネル再生回路の省電力化を提供することにある。(Objective) An object of the present invention is to eliminate the drawbacks of the prior art described above and to provide power saving of a multi-channel reproduction circuit.
（概 要）
本発明の特徴は電圧源と接地間に、型温端子が直列に接
続されたｎ個（ただし、ｎは２以上の整数）の差動増幅
回路、定７ａ流源、該定電流源に直列接続された抵抗の
変化で信号をピックアップするｎ個の手段、前記ｎ個の
差動増幅回路の２人力に、前記抵抗の変化で信号をピッ
クアンプするｎ個の手段のそれぞれの両端の端子を接続
する手段、ならびに少くとも前記電圧源に接続された第
１の差動増幅回路を除く前記差動増幅回路の高電圧体−
低電圧側電源端子間に接続された′、Ｂ量を具備した点
にある。(Overview) The features of the present invention include n differential amplifier circuits (where n is an integer of 2 or more) in which type temperature terminals are connected in series between a voltage source and ground, a constant 7a current source, and a constant 7a current source. n means for picking up a signal by changing a resistance connected in series with a current source; n means for picking up a signal by changing the resistance; means for connecting terminals at both ends, and at least a high voltage body of the differential amplifier circuit other than the first differential amplifier circuit connected to the voltage source;
The present invention is characterized in that it has a quantity ' and B connected between the low voltage side power supply terminals.
（実施例）
以下、本発明の一実施列を第２図によシ説明する。第２
図において、第１図と同−物又は同等物には同一符号が
記されている。(Example) Hereinafter, one embodiment of the present invention will be explained with reference to FIG. Second
In the figures, the same or equivalent parts as in FIG. 1 are designated by the same reference numerals.
まず、本実施例の構成を説明する。定電流源１の一端は
′電圧源１０に接続されており、その他端は第１の磁気
抵抗効果ヘッド２の一方の端子へ接続されている。該第
１の磁気抵抗効果ヘッド２の他端は第２の磁気抵抗効果
ヘッドの一方の端子へ接続されている。以下、同様に第
ｎ番目の磁気抵抗効果ヘッド６まで直列に接続されてお
シ、該第ｎ番目の磁気抵抗効果ヘッド６の他端は接地さ
れている。First, the configuration of this embodiment will be explained. One end of the constant current source 1 is connected to a voltage source 10, and the other end is connected to one terminal of the first magnetoresistive head 2. The other end of the first magnetoresistive head 2 is connected to one terminal of a second magnetoresistive head. Thereafter, they are similarly connected in series up to the nth magnetoresistive head 6, and the other end of the nth magnetoresistive head 6 is grounded.
次に、増幅回路７〜９も上記と同様に接続されている。Next, amplifier circuits 7 to 9 are also connected in the same manner as above.
すなわち、第１の増幅回路７の高圧側電圧端子が電圧源
１０と接続され、低圧側電圧端子は第２の増幅回路８の
高圧側電圧端子と接続されている。該第２の増幅回路８
の低圧（１１１！圧端子は角箱３め増幅回路の高圧側電
圧端子に接続され、以下同様に順次増幅回路は直列接続
されている。そして第ｎ番目の増幅回路９の低圧側電圧
端子は接地されている。That is, the high voltage side voltage terminal of the first amplifier circuit 7 is connected to the voltage source 10, and the low voltage side voltage terminal is connected to the high voltage side voltage terminal of the second amplifier circuit 8. The second amplifier circuit 8
The low voltage (111! voltage terminal) is connected to the high voltage side voltage terminal of the third square box amplifier circuit, and the following amplifier circuits are connected in series in the same way.Then, the low voltage side voltage terminal of the nth amplifier circuit 9 is Grounded.
また、第２番目の増幅回路８から第ｎ番目の増幅回路９
の各々の高電圧−低電圧端子間には容量が接続されてい
る。一方、該増幅回路７，８．９のそれぞれの差動入力
端子には、それぞれ対応した磁気抵抗効果ヘッド２，４
．６の両端子がそれぞれ容量１３〜１７を介して接続さ
れている。Moreover, the second amplifier circuit 8 to the n-th amplifier circuit 9
A capacitor is connected between each high voltage and low voltage terminal. On the other hand, the respective differential input terminals of the amplifier circuits 7, 8.9 are connected to the corresponding magnetoresistive heads 2, 4.
．． Both terminals of 6 are connected via capacitors 13 to 17, respectively.
次に、本実施例の動作について説明する。直列に接続さ
れたｎ個の磁気抵抗効果ヘッド２〜６に、定電流源１か
ら例えば１０ｍＡの電流が供給されている。このため、
磁気抵抗効果ヘッド２〜６が図示されていない磁気テー
プから信号をピックアップすると、該ピックアップされ
た信号は、各増幅回路７〜９の入力端子に接続されたコ
ンデンサ１３〜１７ を介して、増幅回路７〜９のそれ
ぞれに入力する。各増幅回路７〜９は、入力してきた信
号を増幅し、それぞれの出力端から増幅された信号を出
力する。Next, the operation of this embodiment will be explained. A current of, for example, 10 mA is supplied from a constant current source 1 to n magnetoresistive heads 2 to 6 connected in series. For this reason,
When the magnetoresistive heads 2 to 6 pick up signals from a magnetic tape (not shown), the picked up signals are sent to the amplifier circuits via capacitors 13 to 17 connected to the input terminals of each of the amplifier circuits 7 to 9. Enter each of 7 to 9. Each of the amplifier circuits 7 to 9 amplifies the input signal and outputs the amplified signal from its respective output terminal.
この時、入力してきた信号の大きさに応じて増幅回路７
〜９で発生する電流の不平衡は、各増幅回路の電圧源端
子間に挿入された各章１１〜１２により吸収される。At this time, the amplifier circuit 7
The unbalance of the current generated at points 9 to 9 is absorbed by each section 11 to 12 inserted between the voltage source terminals of each amplifier circuit.
例えば、第１の増幅回路７に流れる交流電流（信号電流
）が大きく、そして第２の増幅回路８に流れる交流電流
が小さい場合には、その差分の電流に比例した電荷が容
量１１に蓄積される。逆に、第２の増幅回路８に流れる
交流電流が大きい場合には、第１の増幅回路７から供給
される電流が小さいため、その差分の電流が該容量１１
から供給される。このようにして常に各増幅回路の電流
が平衡に保たれ、安定した動作が行なわれる。For example, when the alternating current (signal current) flowing through the first amplifier circuit 7 is large and the alternating current flowing through the second amplifier circuit 8 is small, a charge proportional to the difference in current is accumulated in the capacitor 11. Ru. Conversely, when the alternating current flowing through the second amplifying circuit 8 is large, the current supplied from the first amplifying circuit 7 is small, and the difference in current is applied to the capacitor 11.
Supplied from. In this way, the currents of each amplifier circuit are always kept balanced, and stable operation is performed.
本実施例によれば、ｎ個の磁気抵抗効果ヘッド。According to this embodiment, there are n magnetoresistive heads.
２〜６のそれぞれの両端が後段の差動増幅回路の２つの
入力端子へ接続されているので、該差動増幅回路では対
応した磁気抵抗効果ヘッドで発生した信号を正確に増幅
することができる。Since both ends of each of 2 to 6 are connected to the two input terminals of the differential amplifier circuit in the subsequent stage, the differential amplifier circuit can accurately amplify the signal generated by the corresponding magnetoresistive head. .
また、ｎ個の磁気抵抗効果ヘッドに１個の定電流源から
電流を供給しているため、定電流源による電力消費が前
述した従来装置の１／ｎになる。さらに、１個の電圧源
１０からｎ個の差動増幅回路７〜９に電力を供給してい
るので、差動増幅回路による電力消費を大幅に削減する
ことができる。Further, since current is supplied to n magnetoresistive heads from one constant current source, power consumption by the constant current source is reduced to 1/n of that of the conventional device described above. Furthermore, since power is supplied from one voltage source 10 to the n differential amplifier circuits 7 to 9, power consumption by the differential amplifier circuits can be significantly reduced.
なお、前記した実施例では入力手段として磁気抵抗効果
ヘッドを例にあげて説明したが、本発明はこれに限定さ
れることなく、いかなる入力手段ｌζも適用することが
できる。Although the above embodiments have been described using a magnetoresistive head as an example of the input means, the present invention is not limited thereto, and any input means lζ can be applied.
（効 果）
以上のように、本発明によれば、磁気抵抗効果ヘッドの
電流源およびそれぞれの増幅回路の電流を１回路分で構
成できる。このため、消費電力を大幅に小さくでき、多
チヤンネル構成を必要とする回路に非常な効果がある。(Effects) As described above, according to the present invention, the current source of the magnetoresistive head and the current of each amplifier circuit can be configured by one circuit. Therefore, power consumption can be significantly reduced, which is very effective for circuits that require a multi-channel configuration.
第１図は磁気抵抗効果ヘッドを用いた従来の多チヤンネ
ル再生回路の一実施例の回路図、第２図は本発明の一実
施例の回路図を示す。
１．３．５・・・定電流源、 ２，４．６・・・磁気抵
抗効果ヘッド、 ？、８．９・・・差動増幅回路、１
１．１２・・・コンデンサ
代理人弁理士 平 木 道 人FIG. 1 is a circuit diagram of an embodiment of a conventional multi-channel reproducing circuit using a magnetoresistive head, and FIG. 2 is a circuit diagram of an embodiment of the present invention. 1.3.5...Constant current source, 2,4.6...Magnetoresistive head, ? , 8.9...Differential amplifier circuit, 1
1.12...Michihito Hiraki, patent attorney representing capacitors
Claims (1)
たｎ個（ただし、ｎは２以上の整数）の差動増幅回路、
定電流源、該定電流源に直列接続された抵抗の変化で信
号をピックアップするｎ個の手段、前記ｎ個の差動増幅
回路のそれぞれの２人力に、前記抵抗の変化で信号をピ
ックアップするｎ個の手段のそれぞれの両端の端子を接
続する手段、ならびに少なくとも前記電圧源に接続され
た第１の差動増幅回路を除く前記差動増幅回路の高電圧
側−低電圧側電源端子間に接続された容量を具備したこ
とを特徴とする多チヤンネル再生回路。 （２）前記抵抗の変化で信号をピックアップする手段が
磁気抵抗効果素子であることを特徴とする特許 回路。[Claims] (N differential amplifier circuits in which power terminals are connected in series between a 1111 pressure source and ground (n is an integer of 2 or more);
a constant current source, n means for picking up a signal by changing a resistance connected in series with the constant current source, and picking up a signal by changing the resistance in each of the n differential amplifier circuits. means for connecting the terminals at both ends of each of the n means, and between the high voltage side and low voltage side power supply terminals of the differential amplifier circuits excluding at least the first differential amplifier circuit connected to the voltage source; A multi-channel reproducing circuit characterized by having connected capacitors. (2) A patented circuit characterized in that the means for picking up a signal by a change in resistance is a magnetoresistive element.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5684183A JPS59185005A (en) | 1983-04-02 | 1983-04-02 | Multi-channel reproducing circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5684183A JPS59185005A (en) | 1983-04-02 | 1983-04-02 | Multi-channel reproducing circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS59185005A true JPS59185005A (en) | 1984-10-20 |
Family
ID=13038622
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5684183A Pending JPS59185005A (en) | 1983-04-02 | 1983-04-02 | Multi-channel reproducing circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS59185005A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0470687A2 (en) * | 1990-08-07 | 1992-02-12 | Seagate Technology International | Magneto-resistive sensor |
-
1983
- 1983-04-02 JP JP5684183A patent/JPS59185005A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0470687A2 (en) * | 1990-08-07 | 1992-02-12 | Seagate Technology International | Magneto-resistive sensor |
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